With the help of Photoshop, German photographer Robert Jahns (aka nois7) has turned photos of breath-taking skylines into heart-stopping images. Using digital manipulation tools, the artist superimposes athletes and daredevils onto birds-eye shots of scenery. The exhilarating final products leave viewers on edge. Some photos depict extreme bikers and boarders doing tricks thousands of feet in the air. Others offer views from front row seats in roller coasters that (hopefully) will never exist.